<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="lib/jquery-3.2.1.js"></script>
    <link rel="stylesheet" href="css/index.css">
</head>
<body>
    <div class="content">
        <div class="bgstyle">
            <div class="kuosan"></div>
        </div>
        <img class="bg" src="images/bg.png" alt="">
        <img class="play-btn" src="images/pause.png" alt="">
        <img class="play-item" src="images/play-item.png" alt="">
    </div>
    <script>
        var isplay = true;
        $(".play-btn").click(function(){
            if(isplay){
                isplay = false
                $(this).attr("src","images/play.png");
                $(".bg").css({animationPlayState:"running"})
                $(".play-item").addClass("play1").removeClass("play2")
                $(".kuosan").addClass("runit")
            }else{
                isplay = true
                $(this).attr("src","images/pause.png");
                $(".bg").css({animationPlayState:"paused"})
                $(".play-item").addClass("play2").removeClass("play1")
                $(".kuosan").removeClass("runit")
            }
        })
    </script>
</body>
</html>